1. Field of the Invention
This invention relates to a battery test unit for testing batteries while stored in a cassette-type package.
Disk-shaped batteries B, typically smaller in diameter than a dime, used to power hearing aids, electrical or electronic watches, flash attachments for cameras, and other small battery powered devices are often packaged for sale and subsequently stored in cassette-type packages such as those shown in FIG. 2. Each battery B has a positive and a negative terminal, b+ and b-, on opposite faces of the disk structure. The cassette-type package generally comprises a housing 2 which includes a cylindrical base 4 and a cover 6 which is formed with a number of individual battery storage compartments 8 arranged in a circular pattern. The cover 6 is free to rotate with respect to the cylindrical base 4 on a central stud 10 so that each battery storage compartment 8 in succession may be positioned over a suitable trap door 12 in the base 4 which permits removal of the stored battery. This trap door 12 is illustrated in detail in FIG. 4. The cover of each storage compartment 8 is provided with a contact access opening 14 which exposes one terminal of the stored battery B.
A conductive base sheet 16 which contacts one terminal of each stored battery is positioned between the assembled cylindrical base 4 and the housing cover 6 and is provided with a tab 18 that projects away from the housing 2. This base sheet 16 may be a cardboard sheet having a coating of aluminum or other conductive metal. Thus, when individual batteries B are stored in this cassette-type package one terminal of each is accessible through the contact access opening in the cover of the corresponding housing compartment and the other terminal of each makes electrical contact with the conductive base sheet 16. An electrical test circuit may then be completed by contacting one terminal of each stored battery through the corresponding contact access opening and by contacting the base sheet tab 18.
The battery test unit of the present invention may be used to quickly, conveniently test batteries while stored in such a cassette-type package at the operator's home or office or at any other location where desired. This case of operation and convenience and the mobility of this battery test unit is particularly important for older persons who must replace dead batteries in hearing aids in order to effectively communicate with other people and who wish to be assured that the replacement battery is fully charged.